Group B Streptococcus - culture

Alternative Names/Synonyms	Group B streptococcus (Streptococcus agalactiae) screen
Laboratory	Microbiology
Sub-section	Bacteriology
Specimen Type	○ Combined vaginal/rectal swab

Other Information

○ This test functions only as a perinatal screen for the presence of Group B streptococcus

○ Group B streptococcal disease in other patients (e.g. nonpregnant adults and neonates) will be identified by routine culture and cannot be ordered separately

○ Cervical, perianal, perirectal, perineal and vaginal (non-introital) swabs are not recommended for Group B streptococcal screening cultures, but will be processed if received by the laboratory

Specimen Requirements (Tube Type)

○ Vaginal (introital)/rectal swab in Amies transport medium (eSwab)

Collection Requirements

○ Collect specimen at 35 to 37 week gestation
○ Swab lower vagina (introitus) followed by the anorectal area using a
single swab. Place swab into Amies transport medium and transport to
the laboratory.

Sample Stability

Refer to section Sample Processing / Delivery

Referral Laboratory

In-house

Laboratory Contact Information

416-586-4800 extension 4507

Approval Required

Sample Processing / Delivery

○ Label specimen container. Place specimens in biohazard bag and seal.

○ Specimens should be stored and transported to the UHN/SH Microbiology Laboratory at room temperature (20-25˚C) after collection